This invention relates to a novel apparatus and method for securing a pipe or work object to prevent it from rotating while applying a torque to the object. The apparatus of this invention has particular application in situations where tradespeople such as plumbers and electricians need to steady a pipe or conduit they are working on.
Workers such as plumbers and electricians sometimes need to hold a work object such as a pipe, conduit, bar, rod or the like steady while applying to it a rotational force, for example to cut or thread a pipe, or to attach or remove a fitting. The known methods for holding a work object steady involve either large, cumbersome devices such as pipe vises which are not easily transported, or are awkward and can involve discomfort to the worker.
There are currently a number of different types of chain vises available in the marketplace which can be used to hold a pipe or other elongated work object in place while cutting it or threading one end, or while tightening or loosening a threaded connection. These vises are typically not easily mobile. While they can be carried between job sites they are typically cumbersome enough that it is not convenient to move them to each location on ajob site where work objects are being handled. On a typical job site where a chain vise is available the worker carries the work object which needs to be secured to the chain vise, performs the required task, and then carries the work object back to the desired location. This is undesirable because the time taken to travel back and forth to the chain vise causes lengthy delays for a worker with a number of tasks to perform on work objects located in a number of different places.
When a worker has a number of small tasks to complete at various locations which require a pipe or work object to be secured, it is common practice to use a pipe wrench to engage the work object. For example, where a worker needs to attach a fitting to a pipe the worker will typically hold the pipe steady by kneeling on the handle of a pipe wrench, with its jaws facing upward engaging the pipe, and while doing so, attach the fitting to the end of the pipe. Needless to say, this method is awkward, requires a certain level of skill and balance, and is difficult for those workers with knee or back problems.
A pipe wrench has a fixed jaw and an adjustable jaw that is also capable of xe2x80x9crockingxe2x80x9d a few degrees so that it uses the principle of a wedge to pinch and therefore hold the work. The more rotational torque applied to the work, the tighter the wrench holds. A pipe wrench is ideally utilized with the jaws facing down so that gravity assists the moveable xe2x80x9crockingxe2x80x9d jaw at the initial gripping of the work. The pipe wrench will also function with the jaws facing upward but the jaws do not firmly grip the work until the rotational torque is applied to cause the xe2x80x9crockingxe2x80x9d jaw to bite into the work via the wrench""s serrated jaws. This means that a second wrench is needed to apply a torque if the pipe wrench is to have the jaws facing upward, making it awkward to perform the required task.
It is known for workers to use various stands or sawhorses when they have to hold or cut a pipe. One example of a portable stand is the Rack-A-Tiers(copyright) (protected by U.S. Pat. No. 5,941,396 entitled WIRE DISPENSER STAND), available from Rack-A-Tiers Mfg. Inc. of Victoria, British Columbia, Canada. This stand is used in pairs as a wire coil holder and it can be used for supporting conduit and pipe for cutting. The worker places the work object in the xe2x80x9cVxe2x80x9d notches on the top of the stand, and either holds it down with one foot, hand or knee, or holds it with a pipe wrench held in one hand while doing work on the work object with a free hand. Gravity holds the work object in the xe2x80x9cVxe2x80x9d notches which prevent the work from rolling off the top of the stands while work is done to the work object. The xe2x80x9cVxe2x80x9d notches do not prevent the conduit from rotating in the xe2x80x9cVxe2x80x9d if rotational torque is applied.
It is also known for workers to use a stand to hold a pipe wrench upright while engaging a pipe so that another pipe wrench can engage the pipe, as disclosed in U.S. Pat. No. 5,791,213 entitled PIPE WRENCH STAND.
There is a strong need for a tool and method that can act as a second set of hands to hold work objects. The tool and method should be both highly portable and easy to use.
This invention provides a method for holding work objects which uses a work object engaging member which preferably comprises a pipe wrench to secure a work object, such as a pipe, conduit, rod, bar, tube or the like in order to prevent the work object from rotating. The wrench has a handle and a mouth, and is engaged by a pivoting member which defines an axis near an end of the handle. The axis is held in fixed or slidable relation to a support. There is a receiving location defined by a notch, recess, protrusion or the like on a top of the support. The work object is held in the receiving location and is prevented from moving laterally. The pivoting member is in a position that allows the wrench to be rotated around the axis so that the mouth of the wrench engages the work object and prevents the work object from rotating in one sense.
By altering the position of the axis relative to the receiving location, the wrench can be used to prevent the work object from rotating in an opposite sense. The invention also provides for employing two wrenches to engage the work object from either side, thereby preventing rotation in either sense. To accomplish this, a second support can be placed adjacent the first support so that the receiving locations of both supports are in alignment, with the second support rotated 180 degrees in relation to the first support. This arrangement allows the first wrench to engage the work object from one side and a second wrench to engage the work object from an opposite side, thereby preventing rotation altogether.
One embodiment of the apparatus comprises a support with a receiving location therein, a work object engaging member, and a pivoting member. The receiving location is capable of receiving a work object, and the pivoting member defines an axis of rotation for the work object engaging member, such that when a work object is disposed in the receiving location, the work object engaging member can be rotated about the axis defined by the pivoting member and engage the work object.
Alternatively, another embodiment of the apparatus comprises the support with the receiving location and the pivoting member configured to be able to accommodate a work engaging member.
A further alternative embodiment of the apparatus comprises a pivoting member configured to accommodate two work engaging members.
One embodiment of the method uses the support with the receiving location, the work engaging member, and the pivoting member, and comprises the steps of engaging the work engaging member with the pivoting member, securing the pivoting member so that it defines an axis, positioning a work object in the receiving location, and rotating the work engaging member about the axis so that it engages the work object.
The invention holds the pipe wrench handle in the manner and orientation in which the operators hand(s) would normally hold the pipe wrench, thus freeing the operator to operate a second wrench or tool. Further aspects and advantages of the invention are set out below.